1、统计出/etc/passwd文件中其默认shell为非/sbin/nologin的用户个数,并将用户都显示出来

       grep -vc "/sbin/nologin" /etc/passwd

      grep -v "/sbin/nologin" /etc/passwd |cut -d: –f1

      
2、查出用户UID最大值的用户名、UID及shell类型

         getent passwd | sort -t: -k3 -nr|head -n1|cut -d: -f1,3,7

       
3、统计当前连接本机的每个远程主机IP的连接数,并按照从大到小排序

      netstat -nt |tr -s " " % |cut -d% -f5|grep -o "[0-9.]\{7,15\}"|sort|uniq -c|sort -nr
4、编写脚本createuser.sh, 实现如下功能: 使用一个用户名作为参数,如果指定参数的用户存在,就显示其存在,否则添加之,显示添加的用户的id号等信息

set -ue
if [ $# -eq 0 ]; then
   { echo "Usage: `basename $0` USERNAME";exit 10; }
elif id $1 &>/dev/null ;then
  { echo "The User is exist !";exit 11; }
elif useradd $1 &>/dev/null ;then
  echo "The user is created,Id is `id -u $1`"                                                        
  fi
5、编写生成脚本基本格式的脚本,包括作者,联系方式,版本,时间,描述等

用户家目录下编辑.vimrc

set ignorecase
set cursorline
set autoindent
autocmd BufNewFile *.sh exec ":call SetTitle()"
func SetTitle()
        if expand("%:e") == 'sh'
        call setline(1,"#!/bin/bash")
        call setline(2,"#")
        call setline(3,"#********************************************************************")
        call setline(4,"#Author:                dingxuetao")
        call setline(5,"#QQ:                    269810520")
        call setline(6,"#Date:                  ".strftime("%Y-%m-%d"))
        call setline(7,"#FileName:             ".expand("%"))                  
        call setline(9,"#Description:          The test script")
        call setline(10,"#Copyright (C):        ".strftime("%Y")." All rights reserved")
        call setline(11,"#********************************************************************")
        call setline(12,"")
        endif
endfunc
autocmd BufNewFile * normal G